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<br />Semple adequacy requirements for affected Brea cover data were <br />calculated using the OSM formula <br />5~t= <br />nmin Idz~ <br />where ^min = the minimum adequate number of cover transacts <br />s= = sample variance <br />t° = a designated t-statistic (0.84 for a one-tailed test <br />with 80;6 confidence) <br />d = desired limits of detection 10.1 or 10`61 <br />x = sample mean <br />2.5.2 Collection and Analysis of Shrub end Tree Data <br />Shrub heights and densities and tree heights, densities, and <br />diameters et breast height IDBH1 were measured at each cover transact loca- <br />tion, In some vegetation types additional sample sites were randomly located <br />to meet sample adequacy requirements. <br />• The crown height of the first two individuals of each shrub <br />species with a canopy overlapping the transact line was measured to the <br />nearest centimeter. Likewise, the height end DBH of the first two indi- <br />viduals of each tree species with canopies overlapping the trensect line <br />were measured. DBH's were recorded t0 the nearest centimeter and heights <br />were estimated to the nearest meter, Accuracy of tree height estimates was <br />improved through the occasional use of en Abney inclinometer, tape measure, <br />end geometry calculations, When the appropriate number of tree or shrub <br />species was not present along the trensect for measurement, those individual <br />tree end shrub species nearest the trensect line were selected and measured. <br />Quadrats were used to collect density data. A rectangular <br />quedret 50 meters by 5 meters was established along the cover trensect. The <br />number of mature (greater than 1.3 meters in height) trees rooted within the <br />quedret was recorded by species. This method was used in all vegetation <br />types except Aspen Forest. Because of the uniform distribution of aspen <br />trees a smaller quadrat 125 meters by 5 meters) was employed. Quadrat <br />size and shape varied for shrub density estimation. A square quadrat <br />5 meters by 5 meters located et the end of the line trensect was used for <br />ell large shrubs in ell vegetation types. A square quadrat 2 meters by <br />2 meters also located et the and of the line trensect was used for deter- <br />mining the density of three small shrubs: Oregon-grape Alchon.ia aep¢nn, <br />Myrtle pechist•ime P¢chu~#.ima my~cai~ci,t¢.o, and a woody Penn#¢mon sp. <br />. Shrub end tree data were analyzed statistically using the same <br />OSM formula es for cover with density used for the mean. <br />-4- <br />